The present disclosure relates to a device which controls a range of vision.
While driving a car, a driver looks through a windshield to check the situation around the car. Japanese Unexamined Patent Publication No. 2016-37201 discloses a device which allows for visual modification of a window frame of a windshield. More specifically, visual modification can be performed by providing a peripheral portion of the windshield with a region in which a range of vision is modified using, e.g., liquid crystals, such that the range of vision is either limited or not. The range of vision is partially limited depending on, for example, driving conditions of the car, road conditions, and the situation around the car.
If a person catches a glimpse of a certain spot at which a large amount of visual features—which are referred to as visual saliency—can be found (high visual saliency), the person's line of sight is prone to be guided toward this specific spot. Visual saliency is defined as conspicuous visual features which change every moment due to color, luminance, inclination of edges, or motion. That is, when a driver looks through the windshield at the conditions ahead, the driver's eyes are prone to be naturally (subconsciously) guided in a direction with a high visual saliency.
However, when a person drives a car and looks through the windshield, which serves as range of vision, at the road conditions ahead, oftentimes the driver's eyes are directed in a completely different direction and the driver does not look at a visual target which requires attention. For example, while driving straight ahead, it can easily happen that the driver's eyes are subconsciously driven toward an eye-catching object (such as a huge illuminated advertising display) at either side of the road.
With the above situation in mind, the present disclosure attempts to provide a device which controls the range of vision such that the driver's eyes can be guided in a desired direction.
The present disclosure proposes the following solution.
A device controlling a range of vision which has a periphery defined by a frame, the device including:
a saliency modifier which modifies visual saliency in a peripheral portion of the range of vision to increase visual saliency in the peripheral portion; and
a controller which controls the saliency modifier based on preset conditions such that the saliency modifier increases visual saliency in a predetermined part of the peripheral portion of the range of vision.
According to the above solution, a person's eyes are easily guided toward a portion with high visual saliency, which is why visual saliency can be effectively used to (subconsciously and calmly) guide the person's eyes in a desired direction. Further, the above solution is beneficial inasmuch as the person's eyes are guided without causing irritation or a sense of discomfort.
Beneficial embodiments of the above solution are described below.
The saliency modifier may increase visual saliency of at least three portions of the range of vision, namely a left edge, a right edge, and a top edge, and
the controller may control the saliency modifier to increase visual saliency of at least one portion selected among the three portions. This embodiment is beneficial inasmuch as it allows for appropriately guiding a person's eyes either to the left, or to the right, or far ahead in a longitudinal direction.
The device may further include:
a gaze direction detector which detects a gaze direction of a person looking through the range of vision at peripheral conditions; and
a visual target detector which detects a visual target a person needs to look at within the range of vision.
When a gaze direction detected by the gaze direction detector indicates that the person's eyes are not directed toward a visual target detected by the visual target detector, the controller may control the saliency modifier to increase visual saliency in a peripheral portion of the range of vision located in a direction leading toward the visual target. This embodiment is beneficial inasmuch as the person's eyes can be guided toward a visual target the person needs to pay attention to and the person does no longer look in a different direction.
The range of vision may be defined as a windshield of a moving object. Since the range of vision, i.e., the windshield, is large, there is a strong tendency of an operator who operates the moving object looking away from a visual target which requires the operator's attention. In this case, however, the operator's eyes can be guided through the windshield in a desired direction.
The controller may increase visual saliency at a top edge of the windshield when the moving object is moving straight ahead. In this case, a person's eyes are guided far ahead of the moving object.
When the moving object is turning, the controller may control the saliency modifier to increase visual saliency of a right or left edge of the windshield, depending on a turning direction. In this case, a person's eyes can be guided toward the turning direction.
The moving object may be a car.
When the moving object is moving sideways, the controller may control the saliency modifier to increase visual saliency of a right or left edge of the windshield, depending on a direction in which the moving object is moving sideways. In this case, a person's eyes can be guided toward the direction in which the moving object is moving sideways.
The range of vision may be a rear view mirror, or a wing mirror, or a display of the moving object, the display showing a set predetermined direction of the moving object. In this case, a person's eyes can be guided in a desired direction within an indirect range of vision.
The saliency modifier may increase a difference in luminance with respect to a background within the range of vision. Since a difference in luminance is easily perceived by the human eye, a person's eyes can be guided highly effectively by modifying the difference in luminance to increase visual saliency.
The saliency modifier may be capable of modifying color. In this case, colors are also used to increase visual saliency. This is beneficial inasmuch as a person's eyes can be guided even more effectively.